COMBIN

Syntax:

COMBIN ( number , number-chosen )

Description: Computes the possible number of groups of size number-chosen that can be formed from number objects.

Note: : A combination is any set or subset of objects, regardless of their internal order. Combinations are distinct from permutations, for which the internal order is significant.

Mathematical Formula:

The number of combinations is as follows, where number = n and number-chosen = k:

where:

Arguments:

Name	Type	Description
number	number	The total number of objects available, truncated to an integer.
number-chosen	number	The number of objects in each combination, truncated to an integer.

Return Type and Value: number – The number of different combinations of number-chosen in number.

However, if

number < 0, #NUM! is returned.
number-chosen < 0, #NUM! is returned.
number < number-chosen, #NUM! is returned.

example: